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Pitco 45C+

I have two Pitco's going off on HL
Both are acting identical where as thermostat is sticking (burner stays on when stat is satisfied, and when temp is turned down).
I condemned the t-stats on both, but one of my customers swears new stat was installed previously with same results. I am now second guessing my diagnosis on both (same models, different customers).
Am I correct in assuming that GV stays open and t-stat opens gas flow?
Is there a Pitco manual more in depth on the gas train/operation?

TIA

Member of the "Work Exchange Program""Will work for knowledge"

"Everyone is a genius. But if you judge a fish on its ability to climb a tree, it will live its whole life believing that it is stupid"
A Einstein

As my own special little tool, I once rigged a ball valve with fittings to pipe in where tstat goes to test the combination valve. Been awhile, but I think the tstat closes to stop flow of bleed gas through it and back to the combination valve - thereby shutting off main burners. That allowed me to place scrutiny on the combination valve ONLY. If I shut it off the ball valve and the burners stayed on, then the combination valve is faulty. Sometimes it took awhile and numerous on/off cycles to catch it.

However, make sure your source & operating gas pressures are good first.

As my own special little tool, I once rigged a ball valve with fittings to pipe in where tstat goes to test the combination valve. Been awhile, but I think the tstat closes to stop flow of bleed gas through it and back to the combination valve - thereby shutting off main burners. That allowed me to place scrutiny on the combination valve ONLY. If I shut it off the ball valve and the burners stayed on, then the combination valve is faulty. Sometimes it took awhile and numerous on/off cycles to catch it.

However, make sure your source & operating gas pressures are good first.

Good info
Valve closed should turn burners off within 15 sec
Would still like to see the breakdown and operation of the gv.
Btw: I went back to one and verified faulty stat.
Will check the other one (different location) tomorrow.
Thanks for sharing the ball valve tool/trick!!!

sent from my Samsung Galaxy Note

Member of the "Work Exchange Program""Will work for knowledge"

"Everyone is a genius. But if you judge a fish on its ability to climb a tree, it will live its whole life believing that it is stupid"
A Einstein